Elite controllers do occur naturally, but such people are unusual. Fewer than one person in 100 seems to have the potential to develop natural elite control. What causes natural elite control remains mysterious, but certain versions of what are known as HLA genes (which regulate cell-surface proteins in some immune-system cells) are rarely found in natural elite controllers. Members of the Visconti cohort did not share this HLA signature. Moreover, their patterns of early infection were different from those of people who go on to become natural elite controllers. In such individuals the virus never really seems to take hold. In members of the Visconti cohort, it did so early and aggressively (one reason why they were treated so quickly in the first place).

Yet, after an average of three and a half years taking antiretroviral drugs, followed by an average of seven and a half years not taking them, the 14 people being followed by Dr Rouzioux and her colleagues show little or no sign of infection. Indeed, the paper suggests, even the low levels of virus still circulating in their bodies seem, in several cases, to be shrinking still further.

The crucial feature shared by people in the Visconti study is that they were put on drugs within ten weeks of infection, a point where the virus is still establishing itself in the body.  This is reminiscent of what has become known as the “Mississippi baby” case, reported earlier this month, in which an infant girl, infected by being born to an HIV+ mother, was given antiretroviral treatment within a few hours of birth. Her doctors, however, lost touch with the child for five months when she was 18 months old, interrupting the treatment. When they reconnected with her they found her infection had regressed to the point of undetectability, even though she was no longer taking the drugs. This observation, combined with the Visconti trial, leads to the question of how frequent the phenomenon of elite control following early treatment actually is.

Elite control does sound incredible, if we can figure out how to harness it.

Thank you for this article!